A cut-off wheel on a grinder or a "muffler chisel" - preterably on an air hammer, also makes muffler repair a lot easier - but the "blue tip wrench" is pretty universal
My 16 year old taurus has stainless exhaust, as does my 22 year old Ranger. So did my Mystique, originally - but when a flange broke for the original owner some bandit sold him a complete walker mild steel system. After I got it, I replaced it again with stainless. The last car s I ownwd without factory stainless exhaust were th '90 aerostar and the '88 New Yorker. My daughres' Honda Civic and Hyundai Elantra both have stainless systems - the Honda's a 2008.